Dyeing of keratin fibers, particularly hair, is known. The desire to alter the color of hair is not a facet of modern times. Hair color is altered to accommodate changes in fashion, style, and personal preference. However, obtaining good coloring and wearability without undesirable side effects to the hair and skin, remains an elusive goal. A suitable method of coloring hair is through oxidative dyeing. A variety of colors may be obtained, including yellows. Although the inventors choose not to speculate on the veracity of the adage according to which reputedly “blondes have more fun,” they do recognize that yellow dyes themselves are desired.
Yellow dyes, particularly those used in coloring hair, should provide good coloring, including intensity of coloration and/or fastness, and be able to perform in spite of external agents, such as light, particularly sunlight, adverse weather conditions, washing and styling, permanent waving, perspiration, and/or friction. Such dyes should also be favourable as to toxicology and dermatology. They should be useful in providing a wide range of shades when combined with other ingredients and process stages, too.
The use of 2-aminophenol (also known as ortho-aminophenol or OAP) and some derivatives thereof, for yellow dyeing of keratin is known. For example, U.S. Pat. No. 4,396,392 (Wella, AG) discloses 2-amino-5-methyl-phenol, WO 02/058,657 (Clairol, Inc.) discloses 2-(amino or amino substituted)-5-methyl-phenol, and DE 202,06,274U1 (Wella, A G) discloses 2,3-diaminophenol derivatives, each for use in providing yellow color, alone and in combination with other coloring agents.
However, many previous oxidative dye compounds and combinations of such compounds resulting in yellow colourations have demonstrated poor wearability and stability to light, and some have recently experienced objections to their use from a toxicological standpoint. OAP, in particular, has been found to provide poor yellow, e.g. with off-tones. One alternative approach has been to use direct non-oxidative dyes alone or in combination with lessened quantities of oxidative dyes. However, this approach has been found to result in poor wash fastness upon shampooing, among other undesirable effects. There remains a need to provide further oxidative dye alternatives to known dyes, preferably yellow dyes, and compositions for dyeing of hair comprising them, that produce good coloration, preferably a bright yellow colouration, that exhibit good dye uptake by the hair, are useful in providing shades or colors which are stable over a reasonable period of time, provide good wash fastness and wearability, good selectivity, do not undergo significant change on exposure to light, shampooing or acid perspiration, and/or exhibit a favourable safety profile.
Compounds according to the following formula are disclosed in JP 63-045,282 (Kanegafuchi Chem. Ind. Co.) as reagents for the synthesis of certain anti-microbial agents, however, not as oxidative dyes:
wherein X1 is O or S; and wherein R1 is selected from formyl, C1 to C3 alkyl substituted with a halogen atom, C1 to C4 acyl, —(CH2)mX2 (wherein m is 1 to 4; X2 is —OH, cyano, C1 to C3 alkoxy, tetrapyranyloxy, C1 to C4 acyl), and salts thereof, as defined therein.
The inventors have surprisingly found that by placing an oxymethyl group at the 5-position (5-oxymethyl) of a 2-(amino or substituted amino)-phenol, compounds exhibiting one or more of the aforementioned desirable qualities may be provided. Without being bound by theory, it is believed that the addition of such a hydrophilic side chain in this position may provide similar or greater coloration and/or wash fastness with improved toxicology versus previous 2-amino phenols and 2-amino phenol derivatives.